//Copyright (c) 2007 Maxence Dislaire

//Permission is hereby granted, free of charge, to any person
//obtaining a copy of this software and associated documentation
//files (the "Software"), to deal in the Software without
//restriction, including without limitation the rights to use,
//copy, modify, merge, publish, distribute, sublicense, and/or sell
//copies of the Software, and to permit persons to whom the
//Software is furnished to do so, subject to the following
//conditions:

//The above copyright notice and this permission notice shall be
//included in all copies or substantial portions of the Software.

//THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
//OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
//HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
//WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//OTHER DEALINGS IN THE SOFTWARE.
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Threading;

namespace YouWebIt
{
    public delegate TReturn FunctionInvoker<TReturn>();

    public static class ProcessHelper
    {
        private static readonly Dictionary<string,Mutex> s_mutexDictionary = new Dictionary<string, Mutex>();

        public static void Register(string name)
        {
            Mutex mutex = new Mutex(true, name);

            if (s_mutexDictionary.ContainsKey(name))
            {
                s_mutexDictionary.Remove(name);
            }
            s_mutexDictionary.Add(name, mutex);
        }

        public static void UnRegister(string name)
        {
            if (s_mutexDictionary.ContainsKey(name))
            {
                Mutex mutex = s_mutexDictionary[name];
                mutex.Close();
                s_mutexDictionary.Remove(name);
            }
        }

        public static bool IsRegister(string name)
        {
            bool createdNew;
            Mutex mutex = new Mutex(true, name, out createdNew);
            if (createdNew)
            {
                mutex.Close();
            }
            return !createdNew;
        }
    }
}
